Hello, Noticing some unexpected behaviours with clear coat shader :
1)Reflections rendering: Clear coat reflections should not be coloured
even if the underlying layer is metallic, see below image example : clear
coat with a rough metallic underlayer in clear skies scenario, works somewhat
well:
cloudy weather scenario , notice the cloud reflections on the clearcoat
layer are coloured in red.However, they should be reflected in their true
colors so clouds should be white as the clear coat itself is not
metallic. Expected reflections
behavior: below is an example of clear coat from other rendering engines.
notice that reflection of underlying metallic layer are bluish , but clear
coat reflections are not.
2)Red channels controls refraction index of clear coat , not clearcoat
amount: It is stated in the documentation that red channels controls
clearcoat amount , however even if completely black clear coat is still
applied and only IOR is affected . while IOR control is very useful , prefer
to have an additional method to control the actual presence of clear coat
altogether. suggestion: use the empty blue channel slot. 3)underlayer IOR
affects clearcoat IOR: if the under layer is non metallic , clear coat IOR
follows the red channel input. However it seems that having the underlayer
metallic directly affects the IOR of the clear coat as well. Reflection on
clear coat becomes more visible at perpendicular viewing angles. Expected
behavior: underlying layer should bear no impact on the clear coat’s IOR. both
should be controlled separately and independently from each other. 4)Normal
Maps are suppressed in clear coat shader: I noticed that clearcoat doesn’t
translate normal details well and suppresses them unless the normal maps are
very strong , I verified that it is not a reflection issues by looking at the
dev mode’s world normals view and verified absence of fine normal details. I
don’t believe this should be the case.